Importance of toxicity testing in drug discovery and research

Toxicity testing plays an essential role in identifying the potential adverse effects caused by chemicals. For instance, genotoxicity, carcinogenicity, immunotoxicity, and reproductive and developmental toxicity in humans are generally observed after chronic chemical exposure. Toxicity testing requires in vitro, in vivo, and in silico methods to assess a chemical or drug candidate hazard. A paradigm shift was observed to reduce the animal usage for toxicity testing by innovative approaches. In this chapter, we discuss the basics concepts of toxicity and types of toxicity. Furthermore, we also discuss the importance of toxicity testing in advancing therapeutic agents and various factors that influence drug toxicity in humans.